洪涝过程探测与准实时服务对于保障人民生命和财产安全意义重大。通常洪涝探测仅关注洪涝断面/平均状态,缺乏对洪涝从发生、发展乃至最后结束的全过程的整体认知,且洪涝探测和服务被动滞后。本文制定洪涝过程探测规则,改进水位预测模型...洪涝过程探测与准实时服务对于保障人民生命和财产安全意义重大。通常洪涝探测仅关注洪涝断面/平均状态,缺乏对洪涝从发生、发展乃至最后结束的全过程的整体认知,且洪涝探测和服务被动滞后。本文制定洪涝过程探测规则,改进水位预测模型,并将其作为理论基础,与传感网信息模型和服务接口相结合,提出了洪涝过程动态探测与准实时服务(process-based flood detection and service,PFD&S)方法。以PFD&S方法为基础,设计并开发了PFD&S原型系统,该系统由传感器层、数据接入层、洪涝探测层和用户交互层4层组成,且具备传感器数据发布和洪涝事件订阅两种使用模式。文中以2016年夏季发生在黄汉流域的洪涝事件为例,对PFD&S方法的可行性和有效性进行验证。结果表明,PFD&S方法和系统能够精准判断洪涝事件所处阶段,并根据不同阶段的需求提供水位预测、洪涝预警或洪涝信息统计等服务,且方法具备准实时性和可扩展性特征。展开更多
The rapid development of Internet technology makes it possible to integrate GIS with the Internet,forming Internet GIS.Internet GIS is based on a distributed client/server architecture and TCP/IP & IIOP.When const...The rapid development of Internet technology makes it possible to integrate GIS with the Internet,forming Internet GIS.Internet GIS is based on a distributed client/server architecture and TCP/IP & IIOP.When constructing and designing Internet GIS,we face the problem of how to express information units of Internet GIS.In order to solve this problem,this paper presents a distributed hypermap model for Internet GIS.This model provides a solution to organize and manage Internet GIS information units.It also illustrates relations between two information units and in an internal information unit both on clients and servers.On the basis of this model,the paper contributes to the expressions of hypermap relations and hypermap operations.The usage of this model is shown in the implementation of a prototype system.展开更多
The paper introduces a new approach, that is, semantic Web techniques, to shed a new light on the solutions for local e-government information portal. After taking the comparison between traditional approaches and sem...The paper introduces a new approach, that is, semantic Web techniques, to shed a new light on the solutions for local e-government information portal. After taking the comparison between traditional approaches and semantic approaches, the design of arehitecture and components of a local e-government information portal are illustrated in details based on semantic technologies. The paper also researches on the core technologies of implementation of the new approach, including the definition of e-government information portal Ontologies and searching algorithms.展开更多
文摘洪涝过程探测与准实时服务对于保障人民生命和财产安全意义重大。通常洪涝探测仅关注洪涝断面/平均状态,缺乏对洪涝从发生、发展乃至最后结束的全过程的整体认知,且洪涝探测和服务被动滞后。本文制定洪涝过程探测规则,改进水位预测模型,并将其作为理论基础,与传感网信息模型和服务接口相结合,提出了洪涝过程动态探测与准实时服务(process-based flood detection and service,PFD&S)方法。以PFD&S方法为基础,设计并开发了PFD&S原型系统,该系统由传感器层、数据接入层、洪涝探测层和用户交互层4层组成,且具备传感器数据发布和洪涝事件订阅两种使用模式。文中以2016年夏季发生在黄汉流域的洪涝事件为例,对PFD&S方法的可行性和有效性进行验证。结果表明,PFD&S方法和系统能够精准判断洪涝事件所处阶段,并根据不同阶段的需求提供水位预测、洪涝预警或洪涝信息统计等服务,且方法具备准实时性和可扩展性特征。
文摘The rapid development of Internet technology makes it possible to integrate GIS with the Internet,forming Internet GIS.Internet GIS is based on a distributed client/server architecture and TCP/IP & IIOP.When constructing and designing Internet GIS,we face the problem of how to express information units of Internet GIS.In order to solve this problem,this paper presents a distributed hypermap model for Internet GIS.This model provides a solution to organize and manage Internet GIS information units.It also illustrates relations between two information units and in an internal information unit both on clients and servers.On the basis of this model,the paper contributes to the expressions of hypermap relations and hypermap operations.The usage of this model is shown in the implementation of a prototype system.
基金Supported by the National Natural Science Foun-dation of China (40501059) the National Basic Research Programof China(973 Program2006CB701305)
文摘The paper introduces a new approach, that is, semantic Web techniques, to shed a new light on the solutions for local e-government information portal. After taking the comparison between traditional approaches and semantic approaches, the design of arehitecture and components of a local e-government information portal are illustrated in details based on semantic technologies. The paper also researches on the core technologies of implementation of the new approach, including the definition of e-government information portal Ontologies and searching algorithms.